Although it doesn't require multiple universes, I derived an alternative path to a finite universe theory by applying symbolic logic to an analysis of fundamental particles.

Here goes:

Fundamental particles are, by their internal and innate nature, necessarily finite. Positing an infinite universe requires assuming the possibility of the existence of infinite quantities of innately finite particles, which renders this position self-contradictory. Therefore, the concept of the necessarily finite universe is tautological (i.e., self-proving).